[Megan]

So currently I have a box that has the following.

The only service is SSH.
To SSH in you need the public key.
To SSH in you need the passphrase.
Passwd login is disabled.
Root login is disabled.

Any suggestions on improvements on how to harden it?

Note: I would change the default port from 22 to something else but for some reason everytime I try it ends up making the box inaccessible from remote SSH, so changing the default port is not really viable at the moment as I am not near the box to fix it.